DTC P2159-00: Vehicle Speed Sensor 'B' Range/Performance(Wheel Speed Sensor): General Description
The Wheel Speed Sensor (WSS) generates a waveform with a frequency proportional to the speed of the vehicle. The signal generated by the WSS informs the ESP module not only if the vehicle speed is low or high but also if the vehicle is or is not moving. Then, ESP module informs ECM of these information.
The ECM uses these information to control the fuel injection, ignition timing, transaxle shift scheduling and torque converter clutch scheduling. The WSS signal is also used to detect rough road conditions.